Ring forming mill



Jan. 8, 1957 E. H. KENDALL RING FORMING-MILL 5 Sheets-Sheet l iled Nov. 30, 1951 INVENTOR EDGAR HOMER KENDALL ATTORNEY Jan. 8, 1957 E. H. KENDALL RING FORMING MILL 5 Sheets-Sheet 2 Filed Nov. 30, 1951 BY W ATTORNEY Jan. 8, 1957 E. H. KENDALL 2,775,535

RING FORMING MILL Filed Nov. 50, 1951 5 Sheets-Sheet 3 INVENTOR H EDGAR HOMER KENDALL ATTORNEY Jan. 8, 1957 E. H. KENDALL RING FORMING MILL 5 Sheets-Sheet 4 On mul m EDGAR HOMER KENDALL Filed Nov. 50, 1951 BY W U4 ATTORNEY Jan. 8, 1957 E. H. KEN DALL RING FORMING MILL 5 Sheets-Sheet 5 Filed Nov. 30, 1951 E M! Y B On ATTORNEY United States Patent 2,776,585 RING FORMING MILL Edgar Homer Kendall, Alliance, Ohio Application November 30, 1951, Serial No. 259,163

11 Claims. (Cl. 86-5) The present invention relates to metal working and forming apparatus, and more particularly to an improved apparatus for forming and sizing large metal rings of the type, for example, utilized in metal wheels for rail-road vehicles and the like.

This invention has as its principal object the provision of novel and improved apparatus for the mass production forming and hot working of tubular steel blanks into accurately dimensioned rings suitable for use, with a minimum of additional finishmachine work, as tires for metal wheels, for example.

In accordance with the above overall object this invention seeks to provide a practical arrangement for forming metal rings wherein heated and pierced metal blanks are simultaneously formed to the desired dimensions of axial length, radial thickness, inside diameter and outside diameter. As will become apparent hereinafter, the apparatus constructed in accordance with the teachings of my invention comprises a plurality of pairs of independently controllable working and forming rolls which may be caused to simultaneously move into working contact with a heated blank and each of which pairs of rolls is operative to form said blank to one of said desired dimensions of axial length, radial thickness, or diameter.

Another object of the present invention is the provision of apparatus embodying teachings as set forth above wherein the various pairs of working and forming rolls are readily adaptable for cooperatively related automatic control whereby each of the said pairs may be caused to form a heated and pierced blank to a desired dimension at a rate which is proportionately related to the forming rate of each of the other pairs. This arrangement provides that a ring being formed in the apparatus will arrive at a finally desired dimension substantially simultaneously along each of its coordinate axes.

Another object of the present invention is the provision of apparatus of the character stated wherein certain novel features of construction are embodied which facilitate and speed the operations of loading the heated blanks and discharging the rings formed therefrom. The arrangement, as will appear, renders my apparatus ideally suited for mass production manufacturing operations.

Yet another object of the invention is the provision of apparatus of the character and for the purpose stated which may be readily adjusted to produce rings of various dimensions between certain maximum and minimum design limits of any particular model of the apparatus.

Yet another object of the invention is the provision of apparatus as above stated wherein the mechanical forces required for working and forming the metal rings are confined to the shortest practicable circuit through the structure of the apparatus. This arrangement permits the structural components of the apparatus to be reduced in mass as will be understood.

A further object of the invention is the provision for use with apparatus of the character described of a novel ice actuating and control system whereby the apparatus may be most advantageously utilized for the purpose intended. Provision is made for maximum productive capacity while keeping instantaneous power demands within reasonable limits, and means is provided to automatically change the effective operating size of the apparatus to correspond with the increased diameter of the ring being formed in the normal operation of the apparatus.

The above and other objects and advantages of the invention will become apparent upon consideration of the following specification and detailed accompanying drawing wherein is shown and described a preferred embodiment of my invention. 7

In the drawing:

Figure 1 is a plan view of a ring forming machine constructed in accordance with the teachings of my invention;

Figure 2 is a side elevation of the apparatus of Figure 1;

Figure 3 is a fragmentary side elevation of structural means forming a part of the apparatus of Figure 1 showing certain details of construction;

Figure 4 is a front elevation of the apparatus shown in Figure 3;

Figure 5 is an enlarged fragmentary section view taken generally along line VV of Figure 4;

Figure 6 is an enlarged fragmentary section view taken generally along line VI-VI of Figure 5;

Figure 7 is a front elevation, partly in section, of a longitudinally movable carriage member of the apparatus of Figure 1 wherein are mounted means for forming a ring to proper dimensions of outside diameter and axial thickness;

Figure 8 is a section view taken along line VIII-VIII of Figure 7; v

Figure 9 is an enlarged fragmentary section view taken along line IX--IX of Figure 7;

Figure 10 is a front elevation, partly in section, of means forming a part of the apparatus of Figure 1 for facilitating the loading of metal blanks into the apparatus and for discharging therefrom the completed rings;

Figure 11 is a pictorial representation of a metal blank being formed into a ring by the apparatus of the present invention; and

Figure 12 is a schematic representation of a control I system which may be used in the operation of the apparatus of Figure 1.

In Figures 1 and 2, the reference numerals 10 and 11 designate a pair of spaced parallel guide rods which are supported above a floor 12 by end stanchions 13 and 14, and intermediate supporting members 15 and 16. The rods 10 and 11 are preferably rigidly secured to the stanchions 13 and 14 and supporting members 15 and 16; the members 13-46 being secured to a floor 12 or other supporting base as will be understood.

Rigidly secured to the end stanchion 13 by means of bolts 17 is a housing 18, the vertically disposed righthand end face of which is provided with guide ways -19 for the reception of a journaling member 20 for a rela tively large diameter forming roll 21. In the preferred form of the invention the journaling member 20 is rigidly secured to the housing 18 by bolts or other suitable means, not shown, but is adapted for easy removal for maintenance and repair by being drawn vertically upward out of the guide ways 19 as will be understood. The roll 21 is journalecl in the member 20 by means of heavy-duty roller bearings 22 as shown in Figure 6, and is provided with means at its lower end shaft portion 23 for connecting the roll 21 to driving means therefor. Such connecting means are shown in Figure 2 and include a speed reducing gear box 24 which is mounted below the general level of the floor 12 and which is in turn connected to a prime mover, as for example an electric motor 25. Any suitable connection may be made between the gear box 24 and the lower end portion 23 of roll 21; it being kept in mind, however, that such means should be readily disconnectible whereby the roll 21 and journaling member 26 therefor may be withdrawn from the guide ways 19 when necessary.

In the forming of metal rings in accordance with the teachings of the present invention the large diameter roll 21 serves as a back-up and drive roll, and adapted for active cooperation with the roll 21, in the manner shown in Figure 11, is a small diameter pressure roll 26 which is adapted to be positioned within the central aperture of a heated metal blank 27 and to be forcibly urged toward the larger roll 21 as the latter is rotated. The rotation of the roll 21 is of course imparted to the blank 27 and the latter is accordingly subjected about its circumferential extent to the working of the cooperating rolls 21 and 26 whereby the radial thickness of the ring 27 may be reduced to the desired dimension.

To mount the pressure roll 26 I provide a pair of U- shaped members 28 positioned one on each side of the roll 21 and having vertically spaced horizontally extending upper and lower leg portions 29 and 30 respectively. Secured between the lower leg portions 30 of the U- shaped members 28 by means of a plurality of bolts 32 is a cross member 31 having a centrally located vertically disposed bore 33 therein for the reception of a spindle member 34 in the manner and for the purpose to be hereinafter explained. Extending between the upper leg portions 29 of the member 28 and secured thereto by means of bolts 35 is an elongated U-shaped member 36 having vertically disposed leg portions 37 as shown in Figure 4. Each of the leg portions 37 is provided with a vertically disposed guideway 38 and the pair of such guideways 38 cooperatively serve to laterally confine a horizontally disposed crosshead 39. The crosshead 39 is provided with a vertically disposed bore 40 which is located in alignment with the bore 33 and which is adapted for the reception of the upper end portion of the spindle member 34 as shown in Figure 6. Preferably, the spindle member 34- is provided with a flange 41 which is adapted to bear against the lower surface of the crosshead 39, and with a suitable aperture near its upper end for the reception of a taper pin or key 42. As appears in Figure 6 the arrangement is such that the key 42, when driven into the aperture therefor, will draw the spindle member upwardly whereby the flange 41 is urged against the lower surface of the crosshead 39 and the spindle member 34 is accordingly rigidly secured to the cross head.

Rotatably journaled on the spindle member 34 by leans of bearings 43 is the small diameter pressure roll 26. The roll 26 is located axially on the spindle by means of the flange 41 and an end cap 44 which is received over the lower end of the spindle 34 and secured thereto as shown in Figure 6. The end cap 44 additionally serves to locate the spindle 34 centrally in the bore 33, and is tapered at its lower end to facilitate entry into the bore as will be understood.

Secured to the upper side of the crosshead 39, substantially directly above the spindle 34, and extending upwardly therefrom, is the piston rod 45 of a hydraulic actuator 46. The actuator 46 is rigidly secured to the vertically disposed U-shaped member 36 and is adapted in response to suitable application of fluid pressure to raise and lower the crosshead 39, and accordingly LEE pressure roll 26. This feature, as will be apparent, per mits the roll 26 to be raised while a heated blank is moved horizontally into forming position. The roll 26 may then be lowered into the eye of the blank and the forming operations initiated.

In order that pressure may be applied between the small and large rolls 26 and 21 I provide means secured to the U-shaped members 28 for effecting horizontal movement of the above described pressure roll mounting assembly toward and away from the center of the largediameter roll 21. In the illustrated embodiment of the invention such means include horizontal disposed connecting rods 47 which are rigidly secured to the vertically disposed back portions of the U-shaped members 28 and which extend through suitable guide cylinders 48 provided therefor in the housing 13. As shown in Figures 1 and 2, the rods 47 extend completely through the housing 18 and are connected at the left hand end thereof by means of a rigid yoke member 4-9. Rigidly connecting the yoke member 49 is the piston rod 50 of a hydraulic actuator 51 which is mounted witl'lin the housing 18 as shown in Figure l. The arrangement is such that application of fluid pressure to the actuator 5.! will effect movement of the yoke, and consequently of the pressure roll 26, either toward or away from the :ooperating large diameter roll 21. And it should be noted that the forces involved in effecting such movement which may be of substantial magnitude during a ring forming operation, are confined wholly within the pressure roll mounting assembly and the housing 18 which is mounted rigidly on the stanchion 13.

To counteract any tendency for an annular blank 27 to crawl upwardly between the rolls 21 and 26 during rotation thereof I have provided a hold-down bar 147 which is rigidly mounted on rods 148 which extend upwardly through suitable apertures therefor in the crosshead 39. Suitable bolts 14% or other locking means are provided to clamp the rods 148 at a predetermined position with respect to the crosshead 3? whereby when the latter is in its lowermost position the hold-down bar 147 will be positioned above and in closely spaced relation to a blank 27 positioned between the rolls 21 and 26.

During a ring forming operation, as the pressure roll 26 is urged toward the large diameter roll 21, a blank 27 will normally tend to expand axially in proportion to the reduction in radial thickness caused by the rolls 21 and 26. To counteract this tendency and to provide means for simultaneously forming the blank 27 to a desired dimension of axial thickness I have provided a pair of edge rolls 52 and 53 which are adapted to act cooperatively on the opposite axial end edges of the blank 27 to confine axial expansion thereof and/or to effect a desired reduction in initial axial dimension as will be understood. In the present embodiment of the invention I have provided for the purpose of mounting the rolls 52 and 53 a carriage 54 which is retained on the guide rods 10 and 11 and is slidable therealong toward and away from the large-diameter main roll 21. The roll 53, which is adapted to act upon the lower end surface of a blank 27 as will appear from Figures 7 and 8, is journaled in a housing 55 therefor, which housing is secured to the carriage 54 by means of bolts 56. [The roll 52 is located directly above the roll 53 and in accordance with the teachings of the invention is adapted to have vertical movement toward and away from the latter roll 53. The vertically movable roll 52 is journaled for rotary movement in a housing 57 which is in turn guided for vertical movement within upwardly extending frame members 58 of the carriage 54 by means of complementary ways '59 and grooves 69 in the frame members 58 and housing 57 respectively.

Extending upwardly and forwardly of the vertically movable housing 57, as an integral part thereof, is a pressure arm 61 the outer end portion of which is located substantially above the roll 52. As appears in Figure 8 a hydraulic actuator 62 is rigidly mounted above the pressure arm 61, and the piston rod 63 extends downwardly into contact with the outer end portion of the arm 61. As will be understood, the application of fluid pressure to the upper end of the actuator 62 will cause a downward pressure to be exerted against the arm 61 and the housing 57 will accordingly be urged downwardly toward the fixed housing 55. The force opposing such downward movement, i. e., the force exerted by the blank 27, is necessarily directed through the roll 52, and accordingly it is important that the actuator rod 63 act on the housing 57 at a point substantially above the 'roll 52 as illustrated.

An adjustable limit to the downward movement of the housing 57 is preferably provided, and in the instant embodiment of the invention this is accomplished by means of a rod 64 which is secured to the housing 57 and which extends upwardly therefrom through a suitable aperture provided in the horizontally disposed cross member 65 which connects the spaced frame members 58 and mounts the actuator 62. The upper end portion of the rod 64 is threaded to receive a similarly threaded nut 66 and lock nut 67 therefor, and it will be understood that the lower limit of movement of the housing 57 may be adjusted to suit various requirements by appropriate adjustment of the nuts 66 and 67.

To raise the housing 57 at the completion of a ring forming operation I have provided an air operated actuator 68 which is secured to the cross member 65 and the piston rod 69 of which is secured to the housing 57 in the manner shown substantially aligned with the center of gravity thereof. Admission of pressurized air into the lower end of the actuator 68 will cause the housing 57 to be raised into its fully retracted uppermost position, and it will be noted that the piston rod 63 of hydraulic actuator 62 will be forced into a retracted position as the housing 57 is raised. The actuator 62 may be of the double acting type if desired whereby the additional actuator 68 may be eliminated, but the illustrated arrangement is preferred in many instances since the downwardly acting force must necessarily act through the outer end portion of the housing 57 while the up wardly acting force is best applied substantially through the center of gravity of the movable assembly.

It is generally preferable to drive the edge rolls 52 and 53 at a rate commensurate with the speed at which the main roll 21 is driven. To this end I have provided a motor 69 and associated speed reducing gear box 70, the latter of which is operatively connected to the edge rolls 52 and 53 at the right hand end of housings 57 and 55 by means of drive shafts 71 and 72 and conventional universal connections 73. The motor 69 and gear box 70 are secured to a platform base 74 which is slidably mounted on the guide rods and 11 and which is rigidly tied to the carriage 54 by means of tie rods 75 which extend between the said carriage and platform and are firmly secured thereto.

Carriage 54, and hence the platform 74 which is secured to the carriage, must be readily adjustable to follow the radial expansion of a blank 27 during a ring forming operation, and to accommodate various initial sizes of the blanks. This adjustment is provided through bydraulic actuator 76 which is mounted on the stanchion 14 at the right hand end of the apparatus. The piston rod 77 of the actuator 76 is connected to the platform 74 and the latter, along with the carriage 54 may be moved toward and away from the main drive roll 21 by suitable application of fluid pressure to the actuator 76, as will be described below.

To retain a blank 27 properly centered in the apparatus during a forming operation, and to confine and regulate the outer periphery of the blank in the manner desired, I have provided a cooperating pair of guide rolls 78 and 79 which rolls are positioned outwardly (to the right) of the main and pressure rolls 21 and 26 and which are adapted to act inwardly upon the outer periphery of a blank 27 substantially toward the center thereof. As will become apparent the guide rolls 78 and '79 operate to restrain the blank 27 as a whole against lateral sideto-side movement and to confine the radial expansion of the blank being formed in such manner as to best suit the end result desired. If desired, and in some applications the same appears necessary, I may employ a second pair of guide rolls, not shown, similar to the rolls 78 and 79, and such additional rolls are preferably carried by hydraulic actuators as described below which in turn are mounted on the fixed housing 18. The four guide rolls thus provided engage the outer periphery of the ring being formed at substantially equally spaced circumferential positions whereby the outer periphery of the ring is held more accurately to a true circle.

In the illustrated embodiment of the invention the rolls 78 and 79 are operated primarily by hydraulic actuators 8i) and 81 positioned at each side of the carriage 54 and angled inwardly with respect to the longitudinal axis of the guide rods 10 and 11 as shown in Figures 1 and 9. Each of the actuators 80 and 81 comprises a generally rectangular guiding member 82 having a rectangular bore therein for the slidable reception of a similarly shaped cylinder member 83. The cylinder member 83 mounts at its outer end extremity one of the guide rolls, as for example guide roll 78 as shown in Figures 7 and 9, and the same is adapted to freely rotate in its mounting as will be understood. The cylinder member 83 is provided with a longitudinal bore 84 extending from its inner end and adapted to receive a piston 85 in the usual manner. In the arrangement shown, however, the piston 85 is rigidly secured to the guide member 82 whereby upon suitable application of fluid pressure to the cylinder 83 the latter, rather than the piston 85, will move inwardly or outwardly to adjust the position of the guide roll 78 as desired.

In the preferred operation of the apparatus it is contemplated that the blanks 27 will be loaded into the forming apparatus horizontally from one side thereof. Accordingly the guide rolls 78 and 79 must be retracted to provide suflicient clearance between the said guide rolls and the main roll 21. For this purpose I have mounted the guide members 82 of the actuators 80 and 81 by means of longitudinally disposed hydraulic actuators 86 and 87 respectively whereby the actuators 80 and 81 may be bodily shifted longitudinally of the apparatus to provide sufiicient clearance to feed a blank 27 into the proper position for the subsequent forming operations or to remove a completed ring 27'.

Actuators 86 and 87 are constructed in a manner similar to actuators 80 and 81; each of the actuators 86 and 87 comprising generally rectangular guide members 88 and 89 mounted on the carriage 54, a similarly shaped cylinder member 90 slidably received in the guide members 88 and 89, and a piston member 91 which is received in a suitable bore 92 provided therefor in the cylinder member and which is rigidly secured to the guide member whereby the cylinder member 90 rather than the piston 91 will move in response to applications of fluid pressure.

It will be understood, of course, that the particular construction of the actuators 80, 81, 86 and 87 herein described is a matter of choice only, and that various other types of actuators may be utilized if appropriate provisions are made for keying or otherwise preventing rotation of the movable parts thereof.

To aid in loading blanks into, and removing completed rings from the apparatus I have provided a table 93 which is positioned adjacent to, and partially surrounding the main and pressure rolls 21 and 26. The table 93 illustrated extends transversely of the principal axis of the apparatus and a short distance outwardly thereof as shown in Figure 10. Preferably conveyors 94 and 95 adjoin the end extremities of the table surface whereby blanks 27 and rings 27' may be moved onto and off of thetable 93 with maximum facility.

In the illustrated embodiment of the invention the upper surface of the table 93 is normally maintained at a level substantially coincident with that defined by the uppermost portion of the periphery of edge roll 53 and by the upper surface of a flanged portion 21' provided at the lower end of the main roll 21. Thus after a blank has been fed into the apparatus and the carriage 54 properly moved into position, the blank will be wholly supported by the edge roll 53 and the flange 21' of the main drive roll 21, and accordingly the table may be lowered away from the blank 27 to prevent possible interference therewith during the forming operation whereby the blank and/ or the table 93 may be damaged.

Means for lowering the table 93 as described above are illustrated in Figure wherein the said table 93 is mounted upon a pair of vertically disposed supports 96 which are located outwardly of the U-shaped members 28 and which are in turn mounted on a horizontal cross bar member 97 which extends between the supports 96 below the lower leg portions 30 of the U-shaped members 28. Secured to the cross bar member 9'! at points adjacent the lower leg portions 30 of members 23 are fluid operated actuators 98 the movable piston members 99 of which are secured to the leg portions 30 of mem ber 28 as shown. it will be observed that suitable application of fluid pressure to actuators 98 will cause the table 93 to move upwardly or downwardly with respect to the Ushaped member 28, and it is contemplated that the upper limit of movement will align the table 93 with conveyors 95 and 96, and with the upper surfaces of roll 53 and flange 21. If desired, spring means such as is generally indicated by the reference numeral 100 may be utilized to normally urge the table 93 toward its upper position.

In the preferred operation of my apparatus a forming operation is begun with the motors and 69 stopped and each of the rolls in a retracted position. To raise table 93 to receive a blank 27 from conveyor 94 switch 101 (see Figure 12) is closed to energize a four-way solenoid valve 102 and appropriately direct the fluid pressure from inlet conduit 1133. A blank 27 is then moved horizontally across the table 93 and positioned directly beneath the pressure roll 26, with is initially in a raised or retracted position. Switch 104 is then closed to open normally closed solenoid valve 105 connecting conduit 107 with conduit 106, the latter of which is in communication with a source, not shown, of hydraulic fluid under pressure as will be understood. The fluid thus admitted into conduit 197 is directed through conduit 1113 and metering valve 109 into the actuator 46 whereby the pressure roll 26 is lowered into its normal position as shown schematically in Figure 11.

Upon the pressure roll 26 reaching its lowermost posi tion fluid pressure within the actuator 46 increases to the pressure of the source, not shown, and causes the actuation of a normally closed pilot operated fluid valve 111 the pilot plunger of which is in communication with the upper end of actuator 46 through conduit 111. Upon opening of valve 110 fluid is directed through conduit 112 and metering valve 113 to actuator 51, and through conduit 114 and metering valve 115 to actuators 86 and 87 which, for purposes of illustration, are shown as conventional movable-piston type actuators.

Fluid thus entering the head end of actuator 51 causes the piston 50 thereof to move to the left to carry the pressure roll 26 toward the main roll 21 and thereby establish a pressure contact with the blank 27. To speed the initial movement of the piston 59 I have provided circuit means including conduits 116 and 117 and solenoid operated valve 118 for directing the fluid exhausted from the rod end of the actuator 51 into the head end thereof whereby a greatly magnified movement is obtained as will be understood. The regenerative circuiting arrangement described is further effective in preventing the premature application of high pressure to the pressure roll 26, and the latter feature is of importance since, as will become apparent, I have found it desirable to accelerate the main roll 21 to full rotational speed before the full operating pressure is applied between the latter and the pressure roll 26 by the movement of pressure roll 26, but after initial contact has been'made with the blank 27.

Fluid entering the actuators 86 and 87 causes operation thereof to effect a forward movement of actuators and 81 at a rate determined by the adjustment of the metering valve 115, and during such forward movement conduit 114 is blocked 011 at its terminus by means of a normally closed pilot operated valve 119.

After actuators 86 and 87 have moved forward as far as possible the fluid pressure in conduit 114 will rise, and such rise will be communicated to the pilot plunger of valve 119 through conduit 120 causing the valve 119 to open. With valve 119 thus opened fluid may pass from conduit 114 through conduit 1211, check valve 122 and conduit 123 into actuators 30 and 81 to effect an inward movement of the guide rolls 78 and 79 in the manner desired until contact is made with the edge of a blank 27.

Upon contact being established between the guide rolls 73 and 79 and a blank 27 a pressure rise occurs in conduit 123 and such rise is communicated through conduit 124 to a pressure responsive switch 125 having normally open contacts 125a and 125. 2. Contacts 125:! and 12512 are interposed between a source of electric potential V and a switching relay 126 which is operative when energized to start motors 25 and 69. Thus when the pressure in conduit 123 rises to a predetermined value, indicating that the pressure roll 26 and guide rolls 78 and 79 are properly positioned with respect to a blank 27, switch 125 closes to energize relay 126 and start the motors 25 and 69. In the illustrated embodiment of the invention I also utilize the closing of pressure switch 125 to energize solenoid valve 118 to block off conduit 117 and connect conduit 116 to exhaust whereby full operating pressure may be applied to the actuator 51 as desired.

In the interest of avoiding undue starting loads on motor 25 and/or motor 69 I have provided a normally open solenoid operated valve 127 in conduit 112 leading to actuator 51. The energizing circuit for the valve 127 includes the normally open contacts 1250 of pressure responsive switch 125 and a pair of normally closed contacts of a speed responsive switch 128 associated with motor 25. The preferred arrangement is such that the valve 127 will be energized upon actuation of pressure responsive switch 125 whereby conduit 112 is blocked off temporarily to prevent full operating pressure from being applied to the actuator 51. After the motor 25 arrives at full operating speed the speed responsive switch 128 opens to deenergize valve 127 and permit pressure to be applied at full value to the actuator 51.

To bring the upper edge roll 52 into contact with the work I have provided a normally closed solenoid operated valve 129 which when energized connects conduit 130 with a source, not shown, of hydraulic fluid. The fluid admitted to conduit 130 passes through a pilot operated valve 131 and conduit 132 into the upper end of actuator 62 to cause downward movement of the plunger 63 thereof and hence the edge roll housing 57. When the roll 52 meets the work the pressure in conduit 132 rises and such rise is communicated through conduit 133 to the pilot plunger of valve 131 causing the valving plunger thereof to move downwardly. With the valving plunger in the downward position the direct connection between conduits 130 and 132 is interrupted and fluid is caused to pass through conduit 134 and metering valve 135 before entering conduit 132. The arrangement, as will be understood, permits rapid movement of the roll 52 into contact with a blank 27 and upon such contact being made automatically shifts the fluid flow through metering valve 135 whereby subsequent downward movement of roll 52 may be accurately regulated. In the present illustration a switch 136 is provided for manually controlling valve 129 but it will be apparent that suitable roll-position detecting devices may be incorporated to render the operation more automatic.

During a ring forming operation, as the radial thickness of a blank is reduced by the pressureroll26 and the axial thickness is similarly reduced by downward movement of the edge roll 52, the blank will expand radially against the restraining pressure of guide rolls 78 and '79. To properly confine and guide the ring during such expansion I have provided the check valve 122 which prevents the passage of fluid in a direction from conduit 123 to conduit 121, and have in. addition provided an outlet conduit 137 having therein a normally closed pilot operated valve 138. Thus as pressure builds up in actuators 8t? and 81 in response to expansive forces exerted by the blank 27, the increase is communicated to the pilot plunger of valve 133 through conduit 139, and at a predetermined pressure the valve 138 opens to permit the guide rolls 78 and 79 to retract.

In the event it becomes desirable to prevent further retraction of the guide rolls 78 and 79 in the forming operation, switch 140 may be closed to energize a normally open solenoid operated valve 141 interposed in conduit 137 whereby no escape passage is provided for the fluid trapped in actuators 80 and 81. The switch 140 in the illustration is manually operated, but it will be apparent that a suitable limit switch, operative to close in response to the blank 27 reaching a predetermined size, may be utilized. The provision of such control arrangements is within the ability of one skilled in the art as will be understood.

To keep the edge rolls 52 and 53 properly positioned with respect to the work as the same expands radially during a ring forming operation I have provided circuit means connecting the actuator 76 for appropriately moving the piston 77 thereof to shift the carriage 54 and platform 74 longitudinally along the guide rods and 11. In the illustration, conduit 142 communicates with a source, not shown, of hydraulic fluid, and through a four-way valve 143 with actuator 76; the position of valve 143 determining the end of actuator 76 to which the inlet pressure is directed. A normally closed solenoidoperated valve 144 is also provided in conduit 145, leading to the head end of actuator 76, for the purpose of blocking or permitting fluid flow to the actuator as desired. Thus with valve 143 in the position shown, energization of valve 144 by closing switch 146 will cause rapid forward movement of the piston 77 to move the carriage 54 into proper position to begin a ring forming the retraction of the carriage during expansion of a blank 27 I have provided a follower valve 150 through which fluid exhausted from the head end of actuator 76 must pass. The follower valve 150 is mounted on the carriage 54 (see Fig. 9) and is adapted to be actuated in response to predetermined movement of a blank 27 with respect to edge rolls 52 and 53. As shown in Figures 7, 8 and 9 the actuating means for valve 150 comprises a work selecting bar 151 which is positioned between rolls 52 and 53 and which is mounted upon slidable rods 152 and 153 extending from the carriage 54. The rod 153 is associated with the operating plunger 150 of valve 150 as shown in Figure 9, and it will be understood that movement of the rod 153 to the left, as caused by radial expansion of a blank 27 against the bar, may be utilized to open valve 150 and cause retraction of the carriage to the position desired.

At the end of a ring forming operation all of the working rolls are rapidly retracted and the motors 25 and 69 are stopped. Circuit and control means for efiecting such operation are not shown, but it will be understood that such means may be provided by a person skilled in the art.

It should now be apparent that I have accomplished the objects initially set forth. The apparatus herein described provides a novel and wholly practical means for forming heated tubular metal blanks into rings suitable for use as, for example, tires for metal wheels. In forming such rings, particularly when the proposed use therefor is metal tires, it is desirable, in addition to forming the blank into the desired shape and size, to mechanically work the material therein to obtain the structural properties required for such use. In the apparatus of my invention a blank may be used which contains the proper volume of material for forming a ring of specified dimen sions, and such blank may be mechanically worked simultaneously along each of its coordinate axes to form a ring having not only the proper dimensions but the desired structural properties as Well. In the apparatus of my invention each of the several pairs of cooperating working and forming rolls are independently controllable whereby a blank may be properly formed to specified final dimensions substantially without regard to the initial proportions of the blank, and it will be understood that by properly adjusting the rates of movement of the various pairs of rolls a blank may be formed into a ring of specified dimensions substantially simultaneously along each of its coordinate axes.

. Within the maximum and minimum limits of the apparatus simple and readily made control adjustments may be made to produce rings of various sizes and proportion, as may be desired. In the event that a large number of rings of the same size are to be formed my apparatus may be readily adapted for fully automatic operation by any person skilled in the art. Of particular importance is the vertical retractible mounting of the working roll 26 which enables the blanks to be automatically loaded in succession by horizontal movement along a conveyor. As one ring is completed the same is pushed out of the way by movement of the next succeeding blank. This saving of time coupled with the time economy resulting from the complete and substantially automatic control of the assembled mill apparatus enables a high rate of production to be maintained with a limited number of operators or attendants.

Regarding the structure of my apparatus, it will be noted that in each instance the pairs of cooperating rolls are so arranged that forces exerted between the rolls are confined to a small circuit and thus undue distortion and/ or failure of the structural elements of the apparatus may be easily prevented without making such elements objectionably large. Note in this respect that the guide rods 16 and 11 serve principally to carry and guide the carriage 54 and platform 74 and that the stanchions l3 and 14, which are rigidly mounted on the floor or other base 12 absorb the greater part of the thrust exerted by actuator 76. It will also be noted that the use of the U- shaped members 28 for mounting the pressure roll 26 permits the same to be drawn inwardly against the main roll 21 by means of an actuator 51 mounted in the same housing as is the roll 21, and thus confines the necessarily high forces involved to the shortest practicable circuit.

It should be understood however, that the specific embodiment of the invention herein disclosed and specifically described is intended to be illustrative only, and reference should therefore be had to the appended claims in determining the scope of the invention.

I claim: 1

1. In apparatus for forming and hot working metal rings having cooperating pressure and anvil rolls disposed in parallel relation and adapted for movement toward and away from each other, said pressure roll being movable longitudinally for insertion into the aperture of an annular metal blank, a pair of auxiliary rolls adapted to have contact with an annular metal blank positioned between said pressure and anvil rolls, and normally inoperative drive means for rotating said anvil roll; the combination of a first fluid actuated cylinder for moving said pressure and anvil rolls toward and away from each other, a second fluid actuated cylinder for moving said pressure roll longitudinally for insertion in the aperture of a blank, a plurality of fluid operated cylinders for moving said auxiliary rolls into and out of contact with said blank, conduit means connecting said second cylinder with a source of fluid under pressure whereby said pressure roll may be caused to move longitudinally into the aperture of said blank, conduit means connecting said source with said first cylinder, conduit means connecting said source with said plurality of cylinders, normally closed valve means positioned in each of said last mentioned conduit means responsive to the positioning of said pressure roll within the aperture of said blank to cause the passage of fluid through said last mentioned conduits to said first and said plurality of cylinders whereby said rolls are moved into contact with said bl solenoid operated valve means asociated with said first cylinder for normally preventing full operating force being applied thereby to said pressure and anvil rolls, pressure responsive switching means operative in response to said auxiliary rolls moving into contact with said blank to start said drive means, and switching means responsive to said drive means attaining operating speed to actuate said solenoid operated valve means whereby said first cylinder is caused to apply full operating force to said pressure and anvil rolls.

2. In apparatus for forming and hot working metal rings the combination of a pair of vertically disposed roll members adapted for relative horizontal movement toward and away from each other, means to rotate one of said roll members, power means for moving said roll members relatively toward each other whereby pressure may be applied to the inner and outer peripheral surfaces of an annular metal blank positioned between said roll members with one of said roll members within the aperture of said blank, a pair of horizontally (lisped edge rolls, means mounting said edge rolls for ver movement toward and away from each other, said rolls being adapted to engage the upper and lower end surfaces of an annular blank positioned between said roll members, means to forcibly urge said edge rolls toward each other, said means for mounting said edge rolls being adapted for horizontal movement toward and away from said roll members power means associated with said last mentioned means for effecting said horizontal movement, a pair of guide rolls positioned one on each side of the axis extending through the centers of said rcll members, power means associated with said guide rolls for moving the same inwardly and outwardly of said axis whereby said guide rolls may be urged into contact with the outer periphery of an annular blank positioned between said roll members, a fixed housing for rotatably supporting said driven roll member, means slidably supported by said housing and rotatably journaling the other of said roll members. said means comprising a pair of Ushaped members positioned one on each side of said roll members and disposed generaly parallel to said axis, said lJ-shaped members having vertically spaced horizontally disposed upper and lower leg portions, a cross member secured to and extending between said lower leg portions and adapted to support the lower end portion of said other roll member, an inverted U-shaped member having vertically disposed leg portions secured to and extending upwardly from the upper leg portions of said pair of U- shaped members, said vertically disposed leg portions having guideways therein, a crosshead slidably retained in said guideways for vertical movement toward and away from said cross member, means in said cross head for supporting the upper end portion of said other roll memher, and means for raising and lowering said crosshead in said guideways whereby said other roll member may be positioned in the aperture of an annular blank, power means for moving said roll members comprising means mounted in said housing and connecting said pair of U-shaped members for moving said pair of U-shaped members horizontally whereby said other roll member may be urged toward said driven roll member.

3. In apparatus of the type described for forming and hot working metal rings and having a vertically disposed pair of working rolls adapted to engage the inner and outer peripheral surfaces of an annular metal blank, means to move said rolls relatively toward or away from each other, and drive means for rotating one of said rolls; the improvement in such apparatus which comprises a control device for said drive means adapted to render the normally inoperative, said control device including means responsive to the movement of said rolls into low pressure contact with an annular blank to start said drive means, means to maintain the pressure contact between said rolls and blank at a low value following the starting of said drive means and while said drive means is accelerating to operating speed, and means responsive to said drive means reaching a predetermined speed to cause full working pressure to be applied to said blank by said rolls.

4. In apparatus for forming and hot working metal rings the combination of a housing, a first roll member rotatably supported on said housing, drive means for rotating said first roll member, a second roll member, journal means movably supported by said housing for journalling said second roll member in parallel relation to said first roll member, said journal means including a pair of spaced cross heads disposed transversely of said second roll member and positioned one near each end thereof, one of said cross heads being movable toward and away from the other in a direction generally parallel with the axis of said first roll member, said second roll member comprising a spindle secured at one end to said movable cross head and slidably received at the other end in said other of said cross heads, said second roll member further comprising a cylindrical roll journalled on said spindle intermediate the ends thereof, means including a horizontal table for moving apertured blanks horizontally and substantially at ring rolling level into longitudinal alignment with said second roll member, means to raise and lower said movable cross head during loading of blanks into alignment with said second roll member, and means to retract said table away from said blank upon the same being gripped in rolling position by said first and second roll members.

5. A ring forming mill comprising a horizontally disposed ring loading support, means to raise and lower said support to and from ring rolling level, horizontal conveyor tables at opposite ends of said support at ring rolling level, a vertically disposed first roll having a ring supporting fiange at its lower end positioned adjacent one side of said support, said ring supporting flange being positioned at ring rolling level, a vertically disposed and vertically movable second roll disposed in parallel relation with said first roll and adapted to engage the inner periphery of a ring lying on said support, means mounting said second roll for longitudinal retracting movement whereby an apertured ring blank may be moved horizontally on said support at ring rolling level into longitudinal alignment with said second roll, vertically spaced rolls positioned adjacent the opposite side of said ring loading support and rotatable about horizontal axes for acting upon the top and bottom surfaces of a ring blank, the lower one of said vertically spaced rolls having an upper peripheral edge substantially at ring rolling level, and means to lower said ring loading table after a ring loading operation whereby said ring is supported during a rolling operation by said flange and the said lower one of said vertically spaced rolls.

6. In a ring forming mill of the type having a first vertically disposed pair of rolls, said first pair of rolls comprising a fixed anvil roll and a pressure roll adapted to engage the inner peripheral surface of an annular blank of metal, and a pair of horizontally disposed edge rolls adapted to engage opposite axial end surfaces of said 13 blank, the improvement which comprises vertically spaced members for mounting said pressure roll at spaced points, one of said members being movable vertically with respect to the other of said members, said pressure roll being mounted on and carried by said movable one of said members whereby upon vertical separating movement of said members said pressure roll is disengaged and separated from the other of said members, a mounting frame for said pressure roll mounting members, said frame having an open side exposing said pressure roll, horizontal blank loading means including conveyor means positioned substantially at the level of the lower one of said pair of edge rolls, said blank loading means being disposed generally transversely with respect to the axes of said edge rolls and extending through said open side, and means to raise said movable one of said members whereby said pressure roll is raised above said blank loading means to provide for the horizontal movement of a ring blank on said loading means, substantially at ring rolling level, into alignment with said pressure roll.

7. Apparatus according to claim 6 further characterized by said pressure roll comprising a spindle and a sleeve rotatably mounted on said spindle, said spindle being fixedly mounted on the said movable one of said members.

8. In apparatus of the type described for forming and hot working metal rings and having a pair of vertically disposed working rolls adapted to engage the inner and outer peripheries of an annular metal blank, the improvement which comprises a flange on one of said working rolls for supporting an annular blank at ring rolling level during rotation thereof between said rolls, a horizontally disposed loading table adapted to support blanks substantially at ring rolling level for loading of the same into said apparatus, said loading table being normally positioned below said flange, and means to raise said loading table substantially to ring rolling level during loading of a blank into said apparatus.

9. Apparatus according to claim 8 further including means to retract one of said working rolls upwardly away from said loading table during loading of a blank, the arrangement being such that a blank may be moved horizontally on said table, substantially at ring rolling level, into alignment with said one of said rolls and said lastmentioned roll thereafter lowered into the eye of said blank.

10. Apparatus according to claim 9 further including means to mount said one of said rolls comprising a horizontally movable lower cross member for engaging the lower end of said one of said rolls, a horizontally and vertically movable upper cross member for engaging the upper end of said one of said rolls, means to move said cross members in unison horizontally toward and away from the other of said rolls, and means to move said upper cross member vertically upward away from said first mentioned cross member, said one of said rolls being separable from said lower cross member and permanently secured to said upper cross member.

11. In apparatus for forming and hot working metal rings and having a first pair of rolls, said first pair of rolls comprising a fixed anvil roll and a vertically retractable pressure roll adapted to engage the inner peripheral surface of an annular blank of metal, a pair of edge rolls adapted to engage opposite axial surfaces of said blank, means to rotate a blank engaged by said pairs of rolls, a plurality of guide rolls adapted to engage the outer peripheral surface of said blank and guide the same during rotation, said first pair and said edge rolls defining a longitudinal axis, said guide rolls being positioned symmetrically on opposite sides of said axis, and means to load blanks into said apparatus; the improvement which comprises first operating cylinders mounting said guide rolls and adapted to move the same radially of a blank engaged by said first pair and said edge rolls, second operating cylinders for said guide rolls, said second cylinders mounting said first cylinders and said guide rolls whereby the latter may be moved bodily in a longitudinal direction to operative and retracted positions, said means to load blanks into said apparatus including conveyor means positioned substantially at the level of the lower one of said edge rolls and positioned adjacent and being transversely disposed of said first pair of rolls, and said second cylinders being operative to move said guide rolls to one side of said transversely disposed conveyor means to facilitate the transverse movement of ring blanks into rolling position in said apparatus when said pressure roll is retracted.

References Cited in the file of this patent UNITED STATES PATENTS 401,713 Munton Apr. 16, 1889 432,625 Kennedy July 22, 1890 949,279 Kennedy Feb. 15, 1910 1,350,057 Bell et al Aug. 17, 1920 1,767,826 Wiles June 24, 1930 1,781,140 Taylor Nov. 11, 1930 1,798,301 Bell Mar. 31, 1931 2,035,598 Eckfeldt et al. Mar. 31, 1936 2,280,783 Bell et al Apr. 28, 1942 2,307,191 Bell Jan. 5, 1943 2,636,406 Salter Apr. 28, 1953 FOREIGN PATENTS 52,173 Germany May 27, 1890 175,359 France Apr. 12, 1886 305,929 Germany June 10, 1918 628,012 Great Britain Aug. 19, 1949 

